Hand instrument for dental care

Abstract

The invention relates to a hand instrument for manual use in dental care, which includes a substantially elongated handle ( 2 ), to at least one end of which is arranged a construction for detachably connecting a head part ( 3 ) extending substantially from the central axis of the handle ( 2 ) and possibly including at least one bending. The construction by which the handle ( 2 ) and the head part ( 3 ) is arranged detachably connected includes a tightening element ( 4 ) axially positioning itself between the handle ( 2 ) and the head part ( 3 ).

The invention claimed is: 
     
       1. A hand instrument for manual use in dental care, comprising:
 a substantially elongated handle having a longitudinal axis, 
 a head-part extending at least substantially from a central axis of the handle, said head-part bent such that at least one region along a length of the head-part resides fully off the longitudinal axis, 
 a construction at one end or both ends of the handle, said construction providing a detachable connection of said head-part to the handle wherein said head-part can be selectively attached to the handle and removed from the handle, the construction including a tightening element, and 
 a fastening element which prevents the head-part from swivelling in relation to the central axis of the handle and a structure which prevents movement of the head-part in an axial direction of the handle when the head-part is positioned in said construction, the fastening element extending substantially from the central axis of the handle, which fastening element is arranged to receive a base end of the head-part, said fastening element including a continuous or discontinuous protrusion configured to engage with a continuous ring-like groove on the head-part, 
 wherein the handle and the tightening element are arranged with compatible threads and the fastening element is integrally formed with the handle, wherein screwing of the tightening element to the handle compresses the protrusion into engagement with said groove and prevents removal of said head-part from engagement with said handle, and 
 
       wherein the fastening element of the handle is arranged with an axially extending axially non-symmetric recess or rib disposed on said longitudinal axis, and the head-part respectively with a rib or a recess that is compatible with the handle recess or rib, which when attached together position the head-part to the handle and prevent swivelling of the head-part in relation to the central axis of the handle. 
     
     
       2. The instrument according to  claim 1 , wherein said tightening element is hollow and the head-part is arranged to extend to the handle through the tightening element. 
     
     
       3. The instrument according to  claim 1 , wherein the tightening element is hollow and a tightening element inner surface includes a thread. 
     
     
       4. The instrument according to  claim 1 , wherein said tightening element includes a handle end and an opposed head-part end and wherein said tightening element includes a hollow region and an inner diameter of said hollow region is arranged to contract towards the head-part end of the tightening element. 
     
     
       5. The instrument according to  claim 1 , wherein the fastening element receiving the head-part comprises a plier-like construction, which is arranged to tighten over the head-part when pressed by the tightening element. 
     
     
       6. The instrument according to  claim 1 , wherein the construction receives a base end of the head-part head-part and wherein said tightening element includes a hollow region defining a female thread, said female thread of said tightening element adapted to receive a corresponding male thread arranged on the handle and tighten over said construction. 
     
     
       7. The instrument according to  claim 1 , wherein the threads of the handle are integrally formed with the handle. 
     
     
       8. The instrument according to  claim 1  wherein said rib or recess of the head-part constitutes an end most element of the head-part. 
     
     
       9. The instrument according to  claim 8  wherein said rib or recess is disposed on said longitudinal axis when attached to the handle. 
     
     
       10. The instrument according to  claim 9  wherein said head-part includes a rib and said fastening element includes a planar recess. 
     
     
       11. The instrument according to  claim 1  comprising the head-part and the construction at both ends of the handle. 
     
     
       12. The instrument according to  claim 1  wherein said head-part comprises one of a tartar scaler and a tooth filling modeller. 
     
     
       13. The instrument according to  claim 1  wherein the tightening element includes a silicone surface. 
     
     
       14. The instrument according to  claim 1  wherein the head-part can be detached from the instrument when said tightening element is loosened but still attached to the handle. 
     
     
       15. A hand instrument for manual use in dental care, comprising:
 a substantially elongated handle having a longitudinal axis, 
 a head-part extending at least substantially from a central axis of both ends of the handle, 
 a construction at both ends of the handle, said construction providing a detachable connection of said head-part to the handle wherein said head-part can be selectively attached to the handle and removed from the handle, the construction including a tightening element, and 
 a fastening element which prevents the head-part from swivelling in relation to the central axis of the handle and a structure which prevents movement of the head-part in an axial direction of the handle when the head-part is positioned in said construction, the fastening element extending substantially from the central axis of the handle, which fastening element is arranged to receive a base end of the head-part, said fastening element including a continuous or discontinuous protrusion configured to engage with a continuous ring-like groove on the head-part, 
 wherein the handle and the tightening element are arranged with compatible threads and the fastening element is integrally formed with the handle, wherein screwing of the tightening element to the handle compresses the protrusion into engagement with said groove and prevents removal of said head-part from engagement with said handle, and 
 wherein the fastening element of the handle is arranged with an axially extending axially non-symmetric recess or rib disposed on said longitudinal axis, and the head-part respectively with a rib or a recess that is compatible with the handle recess or rib, which when attached together position the head-part to the handle and prevent swivelling of the head-part in relation to the central axis of the handle. 
 
     
     
       16. The instrument according to  claim 15  wherein the head-part is bent such that at least at one region along a length of the head-part resides fully off the longitudinal axis. 
     
     
       17. A hand instrument for manual use in dental care, comprising:
 a substantially elongated handle having a longitudinal axis, 
 a head-part selected from a tartar scaler and a tooth filling modeller extending at least substantially from a central axis of the handle, 
 a construction at one end or both ends of the handle, said construction providing a detachable connection of said head-part to the handle wherein said head-part can be selectively attached to the handle and removed from the handle, the construction including a tightening element, and 
 a fastening element which prevents the head-part from swivelling in relation to the central axis of the handle and a structure which prevents movement of the head-part in an axial direction of the handle when the head-part is positioned in said construction, the fastening element extending substantially from the central axis of the handle, which fastening element is arranged to receive a base end of the head-part, said fastening element including a continuous or discontinuous protrusion configured to engage with a continuous ring-like groove on the head-part, 
 wherein the handle and the tightening element are arranged with compatible threads and the fastening element is integrally formed with the handle, wherein screwing of the tightening element to the handle compresses the protrusion into engagement with said groove and prevents removal of said head-part from engagement with said handle, and 
 wherein the fastening element of the handle is arranged with an axially extending axially non-symmetric recess or rib disposed on said longitudinal axis, and the head-part respectively with a rib or a recess that is compatible with the handle recess or rib, which when attached together position the head-part to the handle and prevent swivelling of the head-part in relation to the central axis of the handle.